French hareng, Italian aringa are from Germanic. The Battle of the Herrings (French bataille des harengs) is the popular name for the action at Rouvrai, Feb. 12, 1492, fought in defense of a convoy of provisions, mostly herrings and other "lenten stuffe."
"smoked herring" early 15c. (they turn red when cured), as opposed to white herring "fresh herring." Supposedly used by fugitives to put bloodhounds off their scent (1680s), hence metaphoric sense (1864) of "something used to divert attention from the basic issue;" earlier it simply meant "a false lead":
Though I have not the honour of being one of those sagacious country gentlemen, who have so long vociferated for the American war, who have so long run on the red-herring scent of American taxation before they found out there was no game on foot; (etc.) [Parliamentary speech dated March 20, 1782, reprinted in "Beauties of the British Senate," London, 1786]
fish of the herring family, 1540s, earlier pilcher (1520s), a word of unknown origin, with unetymological -d, perhaps by influence of words in -ard. Century Dictionary suggests Celtic origin, as the fish appear every July in great numbers on the Cornish coast; OED says the Irish word for them is from the English word.
The modern noun usually is a shortening of kippered herring, from a verb meaning "to cure a fish by cleaning, salting, and spicing it" (early 14c.). The earliest attested uses of the verb are to preparing salmon, hence the verb. The modern noun kipper is recorded from 1773 of salmon, 1863 of herring.
"pertaining to the abdomen, ventral," 1550s, from medical Latin abdominalis, from abdomen (genitive abdominis); see abdomen. As a noun, "abdominal muscle," by 1961 (earlier "abdominal vein," 1928); earlier as a fish of the order including carp, salmon, and herring (1835), so called for their ventral fins. Related: Abdominally. English in 17c. had abdominous "big-bellied."